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E Blalock

Publications and source records attributed to E Blalock.

4 recordsLinked to original sources

Identification of an idiotypic peptide recognized by autoantibodies in human immunodeficiency virus-1-infected individuals.

Antibodies against HIV-1 proteins in HIV-1-infected individuals share a cross-reactive idiotype defined by the monoclonal antiidiotypic antibody 1F7 (5). Using a computer algorithm based on the molecular recognition theory, regions of inverse hydropathy between the variable sequence of 1F7 and human monoclonal anti-HIV-1 antibodies were identified, which are assumed to be involved in idiotype-antiidiotype contacts. A peptide was designed from the proposed contact in the variable heavy chain framework 3-complementarity determining region 3 (FR3-CDR3) of human antibodies and was synthesized. This peptide is recognized by the antiidiotype 1F7 and inhibits the binding of 1F7 to human anti-HIV-1 antibodies which express the 1F7 idiotype. A survey of normal and HIV-1-infected sera revealed the presence of antibodies in infected sera which bind to the FR3-CDR3 peptide. The biological relevance of autoantibodies against a self idiotope associated with HIV-1 infection is discussed in the context of the regulation of the antibody response to HIV-1.

Algorithms↗

Shared idiotypy between phosphorylcholine-specific antibody and acetylcholinesterase detectable by a monoclonal antibody.

Studies were undertaken to detect structural similarities between immunoglobulins and other proteins that bind to choline-containing ligands. Such proteins may share serologically detectable determinants that may not be predicted from the amino acid sequence alone. A monoclonal antibody was used that recognizes an idiotope near the phosphorylcholine binding site of the IgA myeloma TEPC15. This monoclonal anti-TEPC15 idiotopic antibody (anti-Id) also bound the enzyme acetylcholinesterase (AChE) as well as the nicotinic acetylcholine receptor from Torpedo californica. The anti-Id antibody also significantly decreased the AChE catalytic activity but did not affect the activity of an unrelated enzyme, horseradish peroxidase. These findings suggest that nonimmunoglobulin molecules share antigenic determinants with immunoglobulin that are associated with binding to structurally related ligands, and immune regulation may inadvertently affect the function of nonimmune systems.

Acetylcholinesterase↗